Radial-radial-axial swirler assembly

ABSTRACT

A swirler assembly for use in a combustor includes a first air swirler having a first swirler vane assembly, a second air swirler adjacent the first air swirler and having a second swirler vane assembly, and a ferrule coupled to the first air swirler and the second air swirler. The ferrule includes a ferrule swirler having a plurality of vanes. The first swirler vane assembly is configured to generate a first radial rotating airflow, and the second swirler vane assembly is configured to generate a second radial rotating airflow. The plurality of vanes of the ferrule swirler are configured to generate a ferrule axial airflow to interact with and mix to with the first radial rotating airflow and the second radial rotating airflow.

TECHNICAL FIELD

The present disclosure relates generally to fuel-air mixer assemblies and, in particular, to a swirler assembly for a fuel-air mixer assembly, and the fuel-air mixer assembly.

BACKGROUND

Engines, and, particularly, gas or combustion turbine engines, are rotary engines that extract energy from a flow of combusted gases passing through the engine onto a multitude of turbine blades. Turbine engines have been used for land and nautical locomotion, and power generation. Turbine engines are commonly used for aeronautical applications such as for aircraft, including helicopters and airplanes. In aircraft, turbine engines are used for propulsion of the aircraft. In terrestrial applications, turbine engines are often used for power generation.

Turbine engines include fuel-air mixer assemblies for mixing fuel and air in a combustion chamber of the turbine engines. The fuel-air mixer assemblies include an air swirler. Combustor performance in the combustion chamber plays an important role in the overall performance of the gas turbine engine.

Combustion performance is in most part controlled by performance of the fuel-air mixer assembly that includes the swirler and involves many competing design objectives. For example, it is desired that the combustion be suitably complete, i.e., rich burn combustion, to reduce exhaust emissions while reducing flame-out effects. Generally, the swirler itself is designed with precision for the operation of mixing compressed air with injected fuel in a manner consistent with desired combustor performance

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other features and advantages will be apparent from the following, more particular, description of various exemplary embodiments, as illustrated in the accompanying drawings, wherein like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements.

FIG. 1 is a schematic diagram of a turbine engine, according to an embodiment of the present disclosure.

FIG. 2 is a cross-sectional view of a portion of a combustor of a combustor assembly of the turbine engine, according to an embodiment of the present disclosure.

FIG. 3 is a cross-sectional view of fuel-air mixer assembly that may be used in the combustor (shown in FIG. 2 ), according to an embodiment of the present disclosure.

FIG. 4 is a perspective cross-sectional view of the fuel-air mixer assembly shown in FIG. 3 , according to an embodiment of the present disclosure.

DETAILED DESCRIPTION

Additional features, advantages, and embodiments of the present disclosure are set forth or apparent from consideration of the following detailed description, drawings, and claims. Moreover, it is to be understood that both the foregoing summary of the present disclosure and the following detailed description are exemplary and intended to provide further explanation without limiting the scope of the disclosure as claimed.

Various embodiments of the present disclosure are discussed in detail below. While specific embodiments are discussed, this is done for illustration purposes only. A person skilled in the relevant art will recognize that other components and configurations may be used without departing from the spirit and scope of the present disclosure.

In the following specification and the claims, reference may be made to a number “optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances in which the event occurs and instances in which the event does not.

Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about”, “approximately”, and “substantially”, are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value. Here and throughout the specification and claims, range limitations may be combined and/or interchanged. Such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise.

As used herein, the terms “axial” and “axially” refer to directions and orientations that extend substantially parallel to a centerline of the turbine engine or the combustor. Moreover, the terms “radial” and “radially” refer to directions and orientations that extend substantially perpendicular to the centerline of the turbine engine or the fuel-air mixer assembly. In addition, as used herein, the terms “circumferential” and “circumferentially” refer to directions and orientations that extend arcuately about the centerline of the turbine engine or the fuel-air mixer assembly.

Embodiments of the present disclosure seek to provide a radial-radial-axial swirler by placing an additional swirler through the ferrule for improving rich-burn combustor flame stability. The swirler within the ferrule, referred herein “ferrule swirler,” can be axial (or at zero-degree angle) relative to a bulk flow direction or at an angle that is radially inward. In an embodiment, vanes of the ferrule swirler can be twisted and shaped for desired vane exit air velocity profile.

The ferrule swirler can be implemented with minimal modifications on rich burn combustors (e.g., straight flow/reverse flow) using traditional manufacturing technology and/or additive technology. The ferrule swirler airflow can be used as a handle to optimize interaction of the airflow through the ferrule swirler with primary swirler airflow. This allows controlling swirler flow aerodynamics that can improve combustion stability and/or improve fuel-air mixing.

FIG. 1 is a schematic diagram of a turbine engine 10, according to an embodiment of the present disclosure. The turbine engine 10 includes a fan assembly 12, a low-pressure or booster compressor assembly 14, a high-pressure compressor assembly 16, and a combustor assembly 18. Fan assembly 12, booster compressor assembly 14, high-pressure compressor assembly 16, and combustor assembly 18 are coupled in flow communication. Turbine engine 10 also includes a high-pressure turbine assembly 20 coupled in flow communication with combustor assembly 18 and a low-pressure turbine assembly 22. Fan assembly 12 includes an array of fan blades 24 extending radially outward from a rotor disk 26. Low-pressure turbine assembly 22 is coupled to fan assembly 12 and booster compressor assembly 14 through a first drive shaft 28, and high-pressure turbine assembly 20 is coupled to high-pressure compressor assembly 16 through a second drive shaft 30. Turbine engine 10 has an intake 32 and an exhaust 34. Turbine engine 10 further includes a centerline (axis) 36 about which fan assembly 12, booster compressor assembly 14, high-pressure compressor assembly 16, and the high-pressure turbine assembly 20 and the low-pressure turbine assembly 22 rotate.

In operation, air entering turbine engine 10 through intake 32 is channeled through fan assembly 12 towards booster compressor assembly 14. Compressed air is discharged from booster compressor assembly 14 towards high-pressure compressor assembly 16. Highly compressed air is channeled from high-pressure compressor assembly 16 towards combustor assembly 18, mixed with fuel, and the mixture of air and fuel is burned within combustor assembly 18. High temperature combustion gas generated by combustor assembly 18 is channeled towards high-pressure turbine assembly 20 and low-pressure turbine assembly 22. Combustion gas is subsequently discharged from turbine engine 10 via exhaust 34.

FIG. 2 is a cross-sectional view of a portion of a combustor 38 of combustor assembly 18 of the turbine engine 10, according to an embodiment of the present disclosure. The combustor 38 defines a combustion chamber 40 in which the highly compressed air is mixed with fuel and combusted. Combustor 38 includes an outer liner 42 and an inner liner 44. Outer liner 42 defines an outer boundary of the combustion chamber 40, and inner liner 44 defines an inner boundary of combustion chamber 40. An annular dome 46 is mounted upstream from outer liner 42 and inner liner 44 and defines an upstream end of combustion chamber 40. One or more fuel injection systems 48 are positioned on annular dome 46. In an embodiment, each fuel injection system 48 includes a fuel nozzle assembly 50 and a fuel-air mixer assembly 52 coupled to fuel nozzle assembly 50. The fuel-air mixer assembly 52 comprises an air swirler 53 that will be described in further detail in the following paragraphs. The fuel-air mixer assembly 52 receives fuel from fuel nozzle assembly 50, receives air from high-pressure compressor assembly 16 (shown in FIG. 1 ) via a diffuser 54, and discharges a fuel-air mixture 56 into combustion chamber 40 where the mixture is ignited using a fuel ignition assembly 60 and burned.

Currently, there are three basic types of air swirlers. In one design, a row of primary apertures discharge jets of primary swirl air followed in turn by a row of secondary radial swirl vanes, i.e., jet-rad design. Fuel is injected at the center of the primary air jets, with the primary jets firstly swirling compressed air around the fuel, with the secondary radial vanes swirling additional air typically in counter rotation with the primary swirl air. The primary jets of swirl air promote stable recirculation zones of the combustion gases inside the combustor dome, and require minimum use of purge air through the fuel injectors.

In a second known design, a row of primary radial swirl vanes replace the primary jets and operate in conjunction with the secondary radial swirl vanes, i.e., rad-rad design, for typically swirling the air in counter rotation around the injected fuel. However, the rad-rad design requires a large amount of purge air from the fuel injectors to produce axial momentum in the fuel and air mixture for establishing the desirable flow structure in the combustor.

A third type of air swirler design is found in a double annular combustor. The air swirler includes primary axial swirl vanes cooperating with secondary radial swirl vanes, i.e., ax-rad design. In this design, the primary vanes directly receive the pressurized air under dynamic pressure thereof with axial momentum through the swirler. However, variations in the dynamic pressure of the compressed air around the circumference of each swirler and around the circumference of the double annular combustor causes variations in performance of the individual swirlers and in the resulting combustor performance.

Accordingly, in order to address the above drawbacks and other drawbacks of the prior air swirler configurations, a different air swirler configuration is provided herein for enhancing combustor performance while reducing purge air requirements, and also reducing manufacturing complexity and swirler cost.

FIG. 3 is a cross-sectional view of fuel-air mixer assembly that may be used in the combustor (shown in FIG. 2 ), according to an embodiment of the present disclosure. FIG. 4 is a perspective cross-sectional view of the fuel-air mixer assembly shown in FIG. 3 , according to an embodiment of the present disclosure. The fuel-air mixer assembly 52 includes an air swirler 102 and a flare cup portion 104 coupled to the air swirler 102. In an embodiment, the air swirler 102 includes a first air swirler 106 (i.e., primary air swirler) and a second air swirler 108 (i.e., secondary air swirler) adjacent the first air swirler 106. The first air swirler 106 includes a first swirler vane assembly 106A positioned therein. The second air swirler 108 includes a second swirler vane assembly 108A positioned therein. In an embodiment, the first swirler vane assembly 106A is configured to generate a first radial rotating airflow 107 and the second swirler vane assembly 108A is configured to generate a second radial rotating airflow 109. In an embodiment, the first swirler vane assembly 106A is configured to turn the first radial rotating airflow 107 in an anti-clockwise direction, and the second swirler vane assembly 108A is configured to turn the second radial rotating airflow 109 in a clockwise direction. In another embodiment, the first swirler vane assembly 106A is configured to turn the first radial rotating airflow 107 in a clockwise direction and the second swirler vane assembly 108A is configured to turn the second radial rotating airflow 109 in an anti-clockwise direction. In an embodiment, the first swirler vane assembly 106A of the first air swirler 106 and the second swirler vane assembly 108A of the second air swirler are configured to turn respective first radial rotating airflow 107 and second radial rotating airflow 109 in a counter-rotating manner.

The fuel-air mixer assembly 52 also includes a ferrule 200 coupled to the air swirler 102. In an embodiment, the ferrule 200 is coupled to the first air swirler 106 and the second air swirler 108. The ferrule 200 includes a fuel nozzle 202. The ferrule 200 includes a ferrule swirler 210. The ferrule swirler 210 has a body 204 having a plurality of vanes 206, as shown in FIGS. 3 and 4 . In place of holes in the body 204 of the ferrule 200, for generating purge air jets, the plurality of vanes 206 are provided instead so as to produce a controlled ferrule axial airflow 201. The plurality of vanes 206 in the body 204 of the ferrule swirler 210 can be configured and positioned for better control of the ferrule axial airflow passing through ferrule 200. The plurality of vanes 206 of the ferrule swirler 210 are configured to guide the ferrule axial airflow to be mixed with the first radial rotating airflow 107 and the second radial rotating airflow 109 and generate an airflow vortex. In an embodiment, the plurality of vanes 206 can be formed by three sides. That is, the radially inner most surface of the swirler vane can be left open and this open side will get closed after assembling the fuel nozzle. The fuel nozzle outer surface will act to close the open side of the swirler vanes. In an embodiment, the plurality of vanes 206 can be configured so that the ferrule axial airflow 201 rotates in a same direction of the first radial rotating airflow 107. In another embodiment, the plurality of vanes 206 can be configured so that the ferrule axial airflow 201 rotates in a same direction of the second radial rotating airflow 109. The first air swirler 106 and a second air swirler 108 together with the ferrule swirler 210 form a swirler assembly 99.

The fuel nozzle 202 in the ferrule 200 is configured to provide a fuel jet 203 for mixing with the ferrule axial airflow 201, the first radial rotating airflow 107 and the second radial rotating airflow 109. The fuel jet 203 is directed to interact with the airflow vortex created by the mixture of the ferrule axial airflow 201 with the first radial rotating airflow 107 and the second radial rotating airflow 109 to generate a controlled fuel-air mixture. In an embodiment, the fuel nozzle 202 in the ferrule 200 is configured to provide the fuel jet 203 for mixing with airflow vortex created by the interaction of the ferrule axial airflow 201 with the first radial rotating airflow 107 and the second radial rotating airflow 109. In an embodiment, a range of flow-splits and swirl number combination between the ferrule swirler 210 and primary swirlers, first air swirler 106 and second air swirler 108, provide stable swirler flow dynamics by interaction between ferrule axial airflow and first radial rotating airflow 107 and second radial rotating airflow 109. In an embodiment, the plurality of vanes 206 can be twisted and shaped for desired level of interaction of ferrule axial airflow 201 with the first radial rotating airflow 107 and the second radial rotating airflow 109.

In an embodiment, the ferrule swirler 210 can be axial relative to a bulk flow direction or generally at an angle that is radially inward, relative to longitudinal axis AA, as depicted for example in FIG. 3 . In an embodiment, the angle of the ferrule axial airflow 201 relative to the longitudinal axis A-A can be in the range between zero degree and sixty degrees. The angle can be selected by selecting an orientation of the plurality of vanes 206 of the ferrule swirler 210. In an embodiment, the plurality of vanes 206 of the ferrule swirler 210 can be twisted and shaped for desired exit velocity profile of the ferrule axial airflow 201. In this respect, the present embodiment has a “radial-radial-axial swirler” configuration in that there are two radial air swirlers corresponding to the first air swirler 106 and the second air swirler 108 and an axial swirler corresponding to the ferrule swirler 210. The term “axial” is used herein to include any angle between zero degree and sixty degrees relative to a longitudinal axis A-A. The term “axial” can also include a “tangential” component. That is, the axial airflow may or may not have a tangential component.

The ferrule swirler can be implemented with minimal modifications on rich burn combustors (straight flow/reverse flow). The ferrule swirler axial airflow can be used as a handle to optimize interaction of the ferrule axial airflow 201 through the ferrule swirler 210 with primary swirler airflows, i.e., first radial rotating airflow 107 and second radial rotating airflow 109. This allows controlling swirler flow aerodynamics that can improve combustion stability and/or improve fuel-air mixing.

In addition, the ferrule 200 is configured to “float” relative to the fuel nozzle 202. The term “float” is used herein to mean that the ferrule 200 can move up and down radially with respect of the longitudinal axis AA in the BB direction generally perpendicular to the longitudinal axis AA, as shown in FIG. 3 .

As a result, the embodiments of the present disclosure described above provide stable swirler flow dynamics. The above described configurations may be suitable for additive build, in any manufacturing method. With additive manufacturing, these configurations can be readily implemented to allow more flexibility in a combustor design. The configurations described above also allow to meet emission requirement while improving durability of the combustor system and engine as whole.

As can be appreciated from the discussion above, a swirler assembly is provided in a combustor. The swirler assembly includes a first air swirler having a first swirler vane assembly, a second air swirler adjacent the first air swirler and having a second swirler vane assembly, and a ferrule coupled to the first air swirler and the second air swirler. The ferrule includes a ferrule swirler having a plurality of vanes. The first swirler vane assembly is configured to generate a first radial rotating airflow. The second swirler vane assembly is configured to generate a second radial rotating airflow. The plurality of vanes of the ferrule swirler are configured to generate a ferrule axial rotating airflow to interact with and to mix with the first radial rotating airflow and the second radial rotating airflow.

The swirler assembly according to the above clause, the first swirler vane assembly being configured to turn the first radial rotating airflow in an anti-clockwise direction, and the second swirler vane assembly is configured to turn the second radial rotating airflow in a clockwise direction or an anti-clockwise direction.

The swirler assembly according to any of the above clauses, the first swirler vane assembly being configured to turn the first radial rotating airflow in a clockwise direction, and the second swirler vane assembly is configured to turn the second radial rotating airflow in an anti-clockwise direction or a clockwise direction.

The swirler assembly according to any of the above clauses, wherein the plurality of vanes of the ferrule swirler are configured so that the ferrule axial airflow rotates in a same direction of the first radial rotating airflow or a same direction of the second radial rotating airflow.

The swirler assembly according to any of the above clauses, wherein the ferrule axial airflow forms an angle relative to a longitudinal axis of the swirler assembly between zero degree and sixty degrees.

The swirler assembly according to any of the above clauses, wherein the ferrule is movable radially in a direction generally perpendicular to a longitudinal axis of the swirler assembly.

The swirler assembly according to any of the above clauses, wherein the ferrule axial airflow interacting with the first radial rotating airflow and the second radial rotating airflow enables controlling swirler flow aerodynamics.

According to another aspect of the present disclosure, a fuel-air mixer assembly for use in a combustor, the fuel-air mixer assembly includes (A) a first air swirler having a first swirler vane assembly, the first swirler vane assembly being configured to generate a first radial rotating airflow, (B) a second air swirler adjacent the first air swirler and having a second swirler vane assembly, the second swirler vane assembly being configured to generate a second radial rotating airflow, and (C) a ferrule coupled to the first air swirler and the second air swirler. The ferrule includes (a) a fuel nozzle configured to generate a fuel jet, and (b) a ferrule swirler having a plurality of vanes, the plurality of vanes of the ferrule swirler being configured to generate a ferrule axial airflow to interact and mix with the first radial rotating airflow and the second radial rotating airflow to generate an airflow vortex. The fuel jet is directed to interact with the airflow vortex to generate a controlled fuel-air mixture.

The fuel-air mixer assembly according to the above clause, wherein the first swirler vane assembly is configured to turn the first radial rotating airflow in an anti-clockwise direction, and the second swirler vane assembly is configured to turn the second radial rotating airflow in a clockwise direction or an anti-clockwise direction.

The fuel-air mixer assembly according to any of the above clauses, wherein the first swirler vane assembly is configured to turn the first radial rotating airflow in a clockwise direction, and the second swirler vane assembly is configured to turn the second radial rotating airflow in an anti-clockwise direction or a clockwise direction.

The fuel-air mixer assembly according to any of the above clauses, wherein the plurality of vanes of the ferrule swirler are configured so that the ferrule axial airflow rotates in a same direction of the first radial rotating airflow or a same direction of the second radial rotating airflow.

The fuel-air mixer assembly according to any of the above clauses, wherein the ferrule axial airflow forms an angle relative to a longitudinal axis of the fuel-air mixer assembly between zero degree and sixty degrees.

The fuel-air mixer assembly according to any of the above clauses, wherein the ferrule is movable radially in a direction generally perpendicular to a longitudinal axis of the fuel-air mixer assembly.

The fuel-air mixer assembly according to any of the above clauses, wherein the ferrule axial airflow interacting with the first radial rotating airflow and the second radial rotating airflow enables controlling swirler flow aerodynamics.

According to another aspect of the present disclosure, a turbine engine includes a combustor comprising a fuel-air mixer assembly and a fuel ignition assembly. The fuel-air mixer assembly includes (A) a first air swirler having a first swirler vane assembly, the first swirler vane assembly being configured to generate a first radial rotating airflow, (B) a second air swirler adjacent the first air swirler and having a second swirler vane assembly, the second swirler vane assembly being configured to generate a second radial rotating airflow, and (C) a ferrule coupled to the first air swirler and the second air swirler. The ferrule includes (a) a fuel nozzle configured to generate a fuel jet, and (b) a ferrule swirler having a plurality of vanes, the plurality of vanes of the ferrule swirler being configured to generate a ferrule axial airflow to interact and mix with the first radial rotating airflow and the second radial rotating airflow to generate an airflow vortex. The fuel jet is directed to interact with the airflow vortex to generate a controlled fuel-air mixture for ignition by the fuel ignition assembly.

The turbine engine according to the above clause, wherein the first swirler vane assembly is configured to turn the first radial rotating airflow in an anti-clockwise direction, and the second swirler vane assembly is configured to turn the second radial rotating airflow in a clockwise direction or an anti-clockwise direction.

The turbine engine according to any of the above clauses, wherein the first swirler vane assembly is configured to turn the first radial rotating airflow in a clockwise direction, and wherein the second swirler vane assembly is configured to turn the second radial rotating airflow in an anti-clockwise direction or a clockwise direction.

The turbine engine according to any of the above clauses, wherein the plurality of vanes of the ferrule swirler are configured so that the ferrule axial airflow rotates in a same direction of the first radial rotating airflow or a same direction of the second radial rotating airflow.

The turbine engine according to any of the above clauses, wherein the ferrule axial airflow forms an angle relative to a longitudinal axis of the fuel-air mixer assembly between zero degree and sixty degrees.

The turbine engine according to any of the above clauses, wherein the ferrule is movable radially in a direction generally perpendicular to a longitudinal axis of the fuel-air mixer assembly.

Although the foregoing description is directed to the preferred embodiments of the present disclosure, it is noted that other variations and modifications will be apparent to those skilled in the art, and may be made without departing from the spirit or scope of the disclosure. Moreover, features described in connection with one embodiment of the present disclosure may be used in conjunction with other embodiments, even if not explicitly stated above. 

1. A swirler assembly for use in a combustor, the swirler assembly comprising: a first air swirler having a first swirler vane assembly, wherein the first swirler vane assembly is configured to generate a first radial rotating airflow, the first radial rotating airflow rotating in a first direction; a second air swirler adjacent the first air swirler and having a second swirler vane assembly, wherein the second swirler vane assembly is configured to generate a second radial rotating airflow, the second radial rotating airflow rotating in a second direction opposite to the first direction; and a ferrule coupled to the first air swirler and the second air swirler, the ferrule comprising a ferrule swirler having a plurality of vanes, wherein the plurality of vanes of the ferrule swirler are configured to generate a ferrule axial airflow having a swirl to interact with and to mix with the first radial rotating airflow and the second radial rotating airflow.
 2. The swirler assembly according to claim 1, wherein the first swirler vane assembly is configured to turn the first radial rotating airflow in an anti-clockwise direction, and wherein the second swirler vane assembly is configured to turn the second radial rotating airflow in a clockwise direction or an anti-clockwise direction.
 3. The swirler assembly according to claim 1, wherein the first swirler vane assembly is configured to turn the first radial rotating airflow in a clockwise direction, and wherein the second swirler vane assembly is configured to turn the second radial rotating airflow in an anti-clockwise direction or a clockwise direction.
 4. The swirler assembly according to claim 1, wherein the plurality of vanes of the ferrule swirler are configured so that the ferrule axial airflow rotates in a same direction of the first radial rotating airflow or the same direction of the second radial rotating airflow.
 5. The swirler assembly according to claim 1, wherein the ferrule axial airflow forms an angle relative to a longitudinal axis of the swirler assembly between zero degree and sixty degrees.
 6. The swirler assembly according to claim 1, wherein the ferrule is movable radially in a direction generally perpendicular to a longitudinal axis of the swirler assembly.
 7. The swirler assembly according to claim 1, wherein the ferrule axial airflow interacting with the first radial rotating airflow and the second radial rotating airflow enables controlling swirler flow aerodynamics.
 8. A fuel-air mixer assembly for use in a combustor, the fuel-air mixer assembly comprising: (A) a first air swirler having a first swirler vane assembly, the first swirler vane assembly being configured to generate a first radial rotating airflow, the first radial rotating airflow rotating in a first direction; (B) a second air swirler adjacent the first air swirler and having a second swirler vane assembly, the second swirler vane assembly being configured to generate a second radial rotating airflow, the second radial rotating airflow rotating in a second direction opposite to the first direction; and (C) a ferrule coupled to the first air swirler and the second air swirler, the ferrule comprising: (a) a fuel nozzle configured to generate a fuel jet, and (b) a ferrule swirler having a plurality of vanes, the plurality of vanes of the ferrule swirler being configured to generate a ferrule axial airflow having a swirl to interact with and to mix with the first radial rotating airflow and the second radial rotating airflow to generate an airflow vortex, wherein the fuel jet is directed to interact with the airflow vortex to generate a controlled fuel-air mixture.
 9. The fuel-air mixer assembly according to claim 8, wherein the first swirler vane assembly is configured to turn the first radial rotating airflow in an anti-clockwise direction, and the second swirler vane assembly is configured to turn the second radial rotating airflow in a clockwise direction or an anti-clockwise direction.
 10. The fuel-air mixer assembly according to claim 8, wherein the first swirler vane assembly is configured to turn the first radial rotating airflow in a clockwise direction, and wherein the second swirler vane assembly is configured to turn the second radial rotating airflow in an anti-clockwise direction or a clockwise direction.
 11. The fuel-air mixer assembly according to claim 8, wherein the plurality of vanes of the ferrule swirler are configured so that the ferrule axial airflow rotates in a same direction of the first radial rotating airflow or a same direction of the second radial rotating airflow.
 12. The fuel-air mixer assembly according to claim 8, wherein the ferrule axial airflow forms an angle relative to a longitudinal axis of the fuel-air mixer assembly between zero degree and sixty degrees.
 13. The fuel-air mixer assembly according to claim 8, wherein the ferrule is movable radially in a direction generally perpendicular to a longitudinal axis of the fuel-air mixer assembly.
 14. The fuel-air mixer assembly according to claim 8, wherein the ferrule axial airflow interacting with the first radial rotating airflow and the second radial rotating airflow enables controlling swirler flow aerodynamics.
 15. A turbine engine comprising: a combustor comprising a fuel-air mixer assembly and a fuel ignition assembly, the fuel-air mixer assembly comprising: (A) a first air swirler having a first swirler vane assembly, the first swirler vane assembly being configured to generate a first radial rotating airflow, the first radial rotating airflow rotating in a first direction; (B) a second air swirler adjacent the first air swirler and having a second swirler vane assembly, the second swirler vane assembly being configured to generate a second radial rotating airflow, the second radial rotating airflow rotating in a second direction opposite to the first direction; and (C) a ferrule coupled to the first air swirler and the second air swirler, the ferrule comprising: (a) a fuel nozzle configured to generate a fuel jet, and (b) a ferrule swirler having a plurality of vanes, the plurality of vanes of the ferrule swirler being configured to generate a ferrule axial airflow having a swirl to interact with and to mix with the first radial rotating airflow and the second radial rotating airflow to generate an airflow vortex, wherein the fuel jet is directed to interact with the airflow vortex to generate a controlled fuel-air mixture for ignition by the fuel ignition assembly.
 16. The turbine engine according to claim 15, wherein the first swirler vane assembly is configured to turn the first radial rotating airflow in an anti-clockwise direction, and wherein the second swirler vane assembly is configured to turn the second radial rotating airflow in a clockwise direction or an anti-clockwise direction.
 17. The turbine engine according to claim 15, wherein the first swirler vane assembly is configured to turn the first radial rotating airflow in a clockwise direction, and wherein the second swirler vane assembly is configured to turn the second radial rotating airflow in an anti-clockwise direction or a clockwise direction.
 18. The turbine engine according to claim 15, wherein the plurality of vanes of the ferrule swirler are configured so that the ferrule axial airflow rotates in a same direction of the first radial rotating airflow or a same direction of the second radial rotating airflow.
 19. The turbine engine according to claim 15, wherein the ferrule axial airflow forms an angle relative to a longitudinal axis of the fuel-air mixer assembly between zero degree and sixty degrees.
 20. The turbine engine according to claim 15, wherein the ferrule is movable radially in a direction generally perpendicular to a longitudinal axis of the fuel-air mixer assembly. 